FFmpeg
af_compensationdelay.c
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1 /*
2  * Copyright (c) 2001-2010 Krzysztof Foltman, Markus Schmidt, Thor Harald Johansen, Vladimir Sadovnikov and others
3  * Copyright (c) 2015 Paul B Mahol
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/opt.h"
23 #include "libavutil/samplefmt.h"
24 #include "avfilter.h"
25 #include "audio.h"
26 #include "internal.h"
27 
28 typedef struct CompensationDelayContext {
29  const AVClass *class;
33  double dry, wet;
34  int temp;
35 
36  unsigned delay;
37  unsigned w_ptr;
38  unsigned buf_size;
41 
42 #define OFFSET(x) offsetof(CompensationDelayContext, x)
43 #define A (AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM)
44 
46  { "mm", "set mm distance", OFFSET(distance_mm), AV_OPT_TYPE_INT, {.i64=0}, 0, 10, A },
47  { "cm", "set cm distance", OFFSET(distance_cm), AV_OPT_TYPE_INT, {.i64=0}, 0, 100, A },
48  { "m", "set meter distance", OFFSET(distance_m), AV_OPT_TYPE_INT, {.i64=0}, 0, 100, A },
49  { "dry", "set dry amount", OFFSET(dry), AV_OPT_TYPE_DOUBLE, {.dbl=0}, 0, 1, A },
50  { "wet", "set wet amount", OFFSET(wet), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, A },
51  { "temp", "set temperature °C", OFFSET(temp), AV_OPT_TYPE_INT, {.i64=20}, -50, 50, A },
52  { NULL }
53 };
54 
55 AVFILTER_DEFINE_CLASS(compensationdelay);
56 
57 // The maximum distance for options
58 #define COMP_DELAY_MAX_DISTANCE (100.0 * 100.0 + 100.0 * 1.0 + 1.0)
59 // The actual speed of sound in normal conditions
60 #define COMP_DELAY_SOUND_SPEED_KM_H(temp) 1.85325 * (643.95 * sqrt(((temp + 273.15) / 273.15)))
61 #define COMP_DELAY_SOUND_SPEED_CM_S(temp) (COMP_DELAY_SOUND_SPEED_KM_H(temp) * (1000.0 * 100.0) /* cm/km */ / (60.0 * 60.0) /* s/h */)
62 #define COMP_DELAY_SOUND_FRONT_DELAY(temp) (1.0 / COMP_DELAY_SOUND_SPEED_CM_S(temp))
63 // The maximum delay may be reached by this filter
64 #define COMP_DELAY_MAX_DELAY (COMP_DELAY_MAX_DISTANCE * COMP_DELAY_SOUND_FRONT_DELAY(50))
65 
67 {
68  AVFilterContext *ctx = inlink->dst;
70  unsigned min_size, new_size = 1;
71 
72  s->delay = (s->distance_m * 100. + s->distance_cm * 1. + s->distance_mm * .1) *
73  COMP_DELAY_SOUND_FRONT_DELAY(s->temp) * inlink->sample_rate;
74  min_size = inlink->sample_rate * COMP_DELAY_MAX_DELAY;
75 
76  while (new_size < min_size)
77  new_size <<= 1;
78 
79  s->buf_size = new_size;
80  s->delay_frame = ff_get_audio_buffer(inlink, s->buf_size);
81  if (!s->delay_frame)
82  return AVERROR(ENOMEM);
83 
84  return 0;
85 }
86 
88 {
89  AVFilterContext *ctx = inlink->dst;
90  AVFilterLink *outlink = ctx->outputs[0];
92  const unsigned b_mask = s->buf_size - 1;
93  const unsigned buf_size = s->buf_size;
94  const unsigned delay = s->delay;
95  const double dry = s->dry;
96  const double wet = s->wet;
97  unsigned r_ptr, w_ptr = 0;
98  AVFrame *out;
99  int n, ch;
100 
101  out = ff_get_audio_buffer(outlink, in->nb_samples);
102  if (!out) {
103  av_frame_free(&in);
104  return AVERROR(ENOMEM);
105  }
107 
108  for (ch = 0; ch < inlink->ch_layout.nb_channels; ch++) {
109  const double *src = (const double *)in->extended_data[ch];
110  double *dst = (double *)out->extended_data[ch];
111  double *buffer = (double *)s->delay_frame->extended_data[ch];
112 
113  w_ptr = s->w_ptr;
114  r_ptr = (w_ptr + buf_size - delay) & b_mask;
115 
116  for (n = 0; n < in->nb_samples; n++) {
117  const double sample = src[n];
118 
119  buffer[w_ptr] = sample;
120  dst[n] = dry * sample + wet * buffer[r_ptr];
121  w_ptr = (w_ptr + 1) & b_mask;
122  r_ptr = (r_ptr + 1) & b_mask;
123  }
124  }
125  s->w_ptr = w_ptr;
126 
127  if (ctx->is_disabled) {
128  av_frame_free(&out);
129  return ff_filter_frame(outlink, in);
130  }
131 
132  av_frame_free(&in);
133  return ff_filter_frame(outlink, out);
134 }
135 
136 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
137  char *res, int res_len, int flags)
138 {
139  CompensationDelayContext *s = ctx->priv;
140  AVFilterLink *outlink = ctx->outputs[0];
141  int ret;
142 
143  ret = ff_filter_process_command(ctx, cmd, args, res, res_len, flags);
144  if (ret < 0)
145  return ret;
146 
147  s->delay = (s->distance_m * 100. + s->distance_cm * 1. + s->distance_mm * .1) *
148  COMP_DELAY_SOUND_FRONT_DELAY(s->temp) * outlink->sample_rate;
149 
150  return 0;
151 }
152 
154 {
155  CompensationDelayContext *s = ctx->priv;
156 
157  av_frame_free(&s->delay_frame);
158 }
159 
161  {
162  .name = "default",
163  .type = AVMEDIA_TYPE_AUDIO,
164  .config_props = config_input,
165  .filter_frame = filter_frame,
166  },
167 };
168 
170  .name = "compensationdelay",
171  .description = NULL_IF_CONFIG_SMALL("Audio Compensation Delay Line."),
172  .priv_size = sizeof(CompensationDelayContext),
173  .priv_class = &compensationdelay_class,
174  .uninit = uninit,
178  .process_command = process_command,
180 };
ff_get_audio_buffer
AVFrame * ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
Request an audio samples buffer with a specific set of permissions.
Definition: audio.c:97
config_input
static int config_input(AVFilterLink *inlink)
Definition: af_compensationdelay.c:66
CompensationDelayContext::distance_mm
int distance_mm
Definition: af_compensationdelay.c:30
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
opt.h
A
#define A
Definition: af_compensationdelay.c:43
out
FILE * out
Definition: movenc.c:54
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1018
ff_af_compensationdelay
const AVFilter ff_af_compensationdelay
Definition: af_compensationdelay.c:169
FILTER_SINGLE_SAMPLEFMT
#define FILTER_SINGLE_SAMPLEFMT(sample_fmt_)
Definition: internal.h:175
inlink
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
Definition: filter_design.txt:212
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:160
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:375
compensationdelay_inputs
static const AVFilterPad compensationdelay_inputs[]
Definition: af_compensationdelay.c:160
AVOption
AVOption.
Definition: opt.h:346
compensationdelay_options
static const AVOption compensationdelay_options[]
Definition: af_compensationdelay.c:45
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:170
COMP_DELAY_MAX_DELAY
#define COMP_DELAY_MAX_DELAY
Definition: af_compensationdelay.c:64
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(compensationdelay)
CompensationDelayContext::delay
unsigned delay
Definition: af_compensationdelay.c:36
samplefmt.h
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:33
av_cold
#define av_cold
Definition: attributes.h:90
s
#define s(width, name)
Definition: cbs_vp9.c:198
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:237
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
CompensationDelayContext::distance_m
int distance_m
Definition: af_compensationdelay.c:32
CompensationDelayContext
Definition: af_compensationdelay.c:28
ctx
AVFormatContext * ctx
Definition: movenc.c:48
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:182
CompensationDelayContext::temp
int temp
Definition: af_compensationdelay.c:34
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_compensationdelay.c:87
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
av_frame_copy_props
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:709
CompensationDelayContext::dry
double dry
Definition: af_compensationdelay.c:33
ff_audio_default_filterpad
const AVFilterPad ff_audio_default_filterpad[1]
An AVFilterPad array whose only entry has name "default" and is of type AVMEDIA_TYPE_AUDIO.
Definition: audio.c:33
CompensationDelayContext::delay_frame
AVFrame * delay_frame
Definition: af_compensationdelay.c:39
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:106
sample
#define sample
Definition: flacdsp_template.c:44
ff_filter_process_command
int ff_filter_process_command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
Generic processing of user supplied commands that are set in the same way as the filter options.
Definition: avfilter.c:890
CompensationDelayContext::w_ptr
unsigned w_ptr
Definition: af_compensationdelay.c:37
internal.h
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:455
AVFrame::extended_data
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:436
COMP_DELAY_SOUND_FRONT_DELAY
#define COMP_DELAY_SOUND_FRONT_DELAY(temp)
Definition: af_compensationdelay.c:62
CompensationDelayContext::wet
double wet
Definition: af_compensationdelay.c:33
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:39
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: af_compensationdelay.c:153
AVFilter
Filter definition.
Definition: avfilter.h:166
ret
ret
Definition: filter_design.txt:187
buffer
the frame and frame reference mechanism is intended to as much as expensive copies of that data while still allowing the filters to produce correct results The data is stored in buffers represented by AVFrame structures Several references can point to the same frame buffer
Definition: filter_design.txt:49
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:235
avfilter.h
AV_SAMPLE_FMT_DBLP
@ AV_SAMPLE_FMT_DBLP
double, planar
Definition: samplefmt.h:67
temp
else temp
Definition: vf_mcdeint.c:263
AVFilterContext
An instance of a filter.
Definition: avfilter.h:407
audio.h
process_command
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args, char *res, int res_len, int flags)
Definition: af_compensationdelay.c:136
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:183
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL
#define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL
Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will have its filter_frame() c...
Definition: avfilter.h:155
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
CompensationDelayContext::distance_cm
int distance_cm
Definition: af_compensationdelay.c:31
CompensationDelayContext::buf_size
unsigned buf_size
Definition: af_compensationdelay.c:38
OFFSET
#define OFFSET(x)
Definition: af_compensationdelay.c:42